HDFS-4096. Add snapshot information to namenode WebUI. Contributed by Haohui Mai.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523091 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5199 Add more debug trace for NFS READ and WRITE. Contributed by Brandon Li

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523140 13f79535-47bb-0310-9956-ffa450edef68
YARN-1116. Populate AMRMTokens back to AMRMTokenSecretManager after RM restarts (Jian He via bikas)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523146 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-9945. HAServiceState should have a state for stopped services. Contributed by Karthik Kambatla.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1523147 13f79535-47bb-0310-9956-ffa450edef68
Merge remote-tracking branch: upstream/trunk